Globally the water production associated with the oil and gas production is more than three times higher than the oil production. This gives an average water fraction of about 75% of what is produced from the wells. The water percentage continues to increase. About ten years ago was it about 70%. The water fraction increases in proportion to the oil fields being older and decreases in proportion to better methods being developed to handle the reservoir and to new fields being introduced. Simultaneously the environmental conditions are being stricter and more complicated to meet. The challenges for the operators are increasing and the need of better, diminished and more cost effective technologies arises. The costs of water treatment participate in determining how high water content it will be profitable to produce. This will also depend on the oil price.